Galvanic cell.



IBEORDUCEE L. KAPLAN, OF BROOKLYN, NEW YORK, ASSIGNOR TO BEACON MINIATURE ELECTRIC CO., INC, 01 NEW YORK, N. Y., A CORPORATION OF NEW YORK.

GA'L'VANIC CELT.

To all whom it may concern:

Be it known'that I, Monnucn L. KAPLAN,

a citizen of the United States, and a resident of Brooklyn, in the county of 'Kmgs and State of New York, have invented certain new and useful Improvements in Galvanic Cells, of which the following is a specification.

The ,galvaniccells of the Leclanch type consist of a negative zinc pole, a positive carbon pole, an electrolyte, containing an ammonia salt, and a depolarizing mass consisting of a mixture of carbon or graphite with a higher oxid of manganese.

.The higher oxids of manganese originally used were the ones contained in the mineral known as'pyrolusite. But this substance 1n order to serve as an efi'ective depolarizer requires pulverization, and'as mechanical pulverizatlon can never be carried far enough to bring all the active ingredients to the surface, only a small fraction of its active principle'was utilized. On this account artificial hydrated manganese came into general use, especially in the manufacture of miniature elements. These substances are obtainable in a very fine state of division but possess other disadvantages, viz. first: small specific weight and second: high percentage of hydrat water, which properties combined make it impossible to crowd sufiicient active material in a small space.

It is the object of my invention to overcome the objections above specified.

- I have discovered that a higher oxid of manganese in a minutest state of'divisi'on and at the same time forming a heavy dense powder suitable for the purpose of being used as a depolarizer in a galvamc cell of the Leclanch type, can be obtained by exposing manganese carbonate to the action Specification'of Letters Patent.

' Patented Apr. H, was.

Application filed August 14, 1913. Serial No. 784,769.

of hot air. I have found also that instead of relying entirely on the action of hot air the carbonate may, with advantage, be first exposed to the oxidizing action of hot air andthe oxidation completed by chemical ox- 1d1z1ng agents such as solutions of permanganate, etc.

I claim:

1 A process for making depolarizing mater al of a dense but highly active character, which consists inexposmg carbonate of manganese to heated air, whereby partial oxidation occurs, and in then subjecting the -.partially oxidized material to the action of a strong oxidizing agent in aqueous solution.

2. A process for making depolarizing material of a dense but highly active porous character, which consists in exposmg a basiccompound of manganese such as the carbonate of manganese to a gaseous oxidizing agent, whereby a substantial measure of oxidation occurs, and in further oxidizing the product by treatment with an aqueous solution of an oxidizing agent.

3. A process for making depolarizing material of a dense but highly active character adapted for use in miniature dry batteries, which consist in subjecting a basic compound of manganese to dry oxidation, whereby highly active compounds of manganese are formed. of a dense character, and in further oxidizing the product by wet oxidation.

Signed at New York, in the county of New York, and State of New York, this 13th day of August, A. D. 1913.

MORDUOH L. KAPLAN. 

